The conversion between rotational power and electrical power has very early beginnings. The first electrical generator demonstrated was a “Faraday Disk” developed by Michael Faraday between 1831 and 1832. Also in 1832 the “Dynamo” was introduced by Hippolyte Pixii and thus demonstrated the generator system used in industry having a field, rotor and commutator most of which are still common in modern generators, alternators and motors. During this same year 1832, a British inventor named William Sturgeon demonstrated the first direct current (DC) motor capable of turning machinery and soon after in 1837, Emily and Thomas Davenport patented the first commercialized version of the commutator type DC electric motor.
Most modern electrical generators and motors resemble the early ones with the exception of vast improvements in “air gap” distances where the older machines lost huge amounts of efficiency due to large “air gaps”. Other advancements have been made to improve efficiency and commercial value throughout the years.